Your alarm is set for your 6 a.m. workout, and you responsibly slip into bed exactly eight-and-a-half hours before you have to wake up. But you're still awake a few hours later, thinking obsessively about an argument you had with a friend before moving on to a stressful meeting you have planned with your boss the next day. You finally fall asleep at 3 a.m., only to be woken up by the blaring sound of your alarm a mere three hours later. You know your body could do with the two hours of extra sleep you could get if you just skipped your workout, but you drag yourself out of bed anyway, reminding yourself that you committed to getting more exercise this year.

We've all had to choose between sleep and exercise at some point, and you're probably familiar with feelings of intense hunger throughout those exhausting days. That could have something to do with the tough workout you put in that morning, but more likely it's because, as a 2010 University of Chicago study shows, the hunger hormone ghrelin kicks into high gear when we're sleep-deprived.

Not only can this lead to even lower levels of energy due to the unhealthy food we may mindlessly reach for when we're tired, but it can lead to weight gain. And while we know exercise plays a small role in weight loss and a potentially larger one in weight maintenance, when it comes to reaching a healthy weight, what's the more important piece of the puzzle?

Deciding between a full night of sleep and a workout.

Samantha Schmuck, a health coach at Health Coach Institute, explains that sleep and exercise actually work together quite well: When you're getting enough exercise, you'll fall asleep more easily and sleep more deeply, and when you're getting enough sleep, your workouts will be stronger.

"From a physiological perspective, exercise helps regulate different chemicals in your body that can either inhibit or promote sleep—otherwise known as the circadian rhythm," she explains. "While this process is largely responsible for helping you get enough sleep, another main culprit that exercise can help counteract is stress."

If you absolutely have to choose between the two, according to Schmuck, the smartest thing you can do is ask yourself what your body is craving at that point in your life. "If you are in a high-stress period of your life, then intense workouts may be too much for your body at that time. Take a step back, breathe, assess what is true for you in your life, and take action that honors what your unique body needs each day in order to thrive."

In other words, if you're going through a period of extreme stress, a long, intense workout may lead to excess cortisol in the body, which we know is correlated with weight gain. In that case, opt for a yoga class and an extra hour of sleep.

Sleep is crucial to the recovery process.

If your goals are less about weight loss and more about building stronger muscles, remember this: Sleep is absolutely crucial to the recovery process. "The human body undergoes billions of chemical reactions each day to maintain homeostasis, all of which require varying levels of energy," explains Schmuck. "When you are drawing from low reserves due to a consistent lack of sleep or a high-stress time in your life, exercise does not necessarily rank high in terms of where your body would prefer to divert energy."

So no matter how dedicated you are to your exercise routine, if you're consistently getting less than seven hours of sleep per night, your muscles will fatigue more easily and your coordination and agility will be compromised, increasing your risk of injury. That's not good news for anyone.

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So, what's the answer?

The answer to the sleep-versus-exercise debate, according to Schmuck, is that a thought process like that needs to be eliminated altogether. "You just have to say to yourself, 'either I get a full night of sleep and have a killer workout, or I don’t sleep well and so I'm going to skip my workout today.' Both sleep and exercise are essential to living a healthy lifestyle and maintaining a healthy weight, and being able to find the right balance between the two, when life is not perfect, is key."